Hmm... But I could just use .2 as an approximation, right? I've already spent a few days poking at this project, so I'm okay with 'pretty darn close'. And the outcome will be in newtons (.001 of kN). Bringing up another thing... Just out of curiosity, why wasn't the '(GM)/r2'(found in the 2ndand 3rd) divided from both sides? and if '(GM)/r2' were to be represented by a single value, how would it be written as it is in the 3rd equation?